含硫易切削钢夹杂物控制试验研究

通过高温试验研究了钙处理和镁处理对含硫易切削钢中夹杂物的控制效果。钙处理后钢中夹杂物为CaAl-O+(Ca,Mn)S复合夹杂物、(Ca,Mn)S以及Mn S夹杂物;镁处理后钢中夹杂物为Mg Al2O4+(Mg,Mn)S、Al2O3+Mn S复合夹杂物、(Mg,Mn)S以及Mn S夹杂物。钙处理和镁处理后钢中的复合夹杂物所占比例分别为0.67%和3.57%。镁处理后钢中Ⅱ类Mn S夹杂物明显减少,91.7%的夹杂物尺寸小于3μm,纺锤率达到72.5%,其对夹杂物的控制效果优于钙处理。

Experimental Study on Inclusions Control of Resulfurized Free Cutting Steel

In this paper,the effects of calcium treatment and magnesium treatment on characters of inclusions in resulfurized free cutting steels were studied by high temperature experiments.The results show that the main types of inclusions after calcium treatment are Ca-A1-O+(Ca,Mn)S complex inclusions,(Ca,Mn)S and MnS.Meanwhile,the main types of inclusions after magnesium treatment are Mgal2O4 + (Mg,Mn) S,A12 O3 +MnS complex inclusions,(Mg,Mn) S and MnS.The proportions of complex inclusions after calcium treatment and magnesium treatment are 0.67％ and 3.57％,respectively.The amounts of type Ⅱ MnS inclusions in the steel are obviously reduced after Mg treatment,and 91.7 ％ of the inclusions are smaller than 3 μm in size.Furthermore,the ratio of spindle inclusions reached 72.5％.Therefore,the effect of controlling inclusions by magnesium treatment is superior to calcium treatment.